Fish are an essential source of global food. Fishery‐independent data is critical to fisheries assessment and management. The uncertainties created by changing methods to collect this data must be understood. In the U.S. Northeast Atlantic, a drop camera survey of Atlantic sea scallops is a critical source of fishery‐independent data. From 1999 to 2016 the primary sampling unit of the survey was an

Manganese oxide minerals (Mn(III/IV)Ox) are ubiquitous in natural environments and interactions between Mn(III/IV)Ox and microbes play important roles in biogeochemical cycles. Current techniques for determining the spatial distribution of microbes with Mn(III/IV)Ox include electron microscopy and synchrotron radiation analyses. However, these techniques may not be readily available in most laboratories

Isoprene is a biogenic volatile organic compound (BVOC), which is predominantly emitted by terrestrial plants but also from marine systems. However, the marine contribution to isoprene emissions is less understood due to the difficulty of measuring trace concentrations in seawater. Previous methods using “purge and trap” coupled with flame ionization detection and/or chemiluminescence have been developed

Fatty acid (FA) compositions provide insights about storage and feeding modes of marine organisms, characterizing trophic relationships in the marine food web. Such compositional data, which are normalized to sum to 1, have values—and thus derived statistics as well—that depend on the particular mix of components that constitute the composition. In FA studies, if the set of FAs under investigation

There is keen interest to enhance denitrification within intervening aquatic habitats between agricultural areas and downstream aquatic ecosystems to reduce nitrogen (N) loading impacts to receiving ecosystems. We conducted a series of measurements to examine whole system in situ diel denitrification estimates in experimental ditch and stream environments using a Bayesian one‐station diel N2 flux model

Compound‐specific isotopic analysis of amino acids (CSIA‐AA) is increasingly used in ecological and biogeochemical studies tracking the origin and fate of nitrogen (N). Its advantages include the potential for resolving finer‐scale trophic dynamics than possible with standard bulk SIA and for reconstructing historical changes in the food webs of consumers from analyses of specimens in preserved sample

Strontium/calcium ratios (Sr/Ca) in reef coral skeletons have been used for sea surface temperature (SST) proxy. Because skeletons of reef corals are accumulated throughout more than 100 years, SST records from coral skeletons were important archives to reveal climate mechanisms. Here, we improved the coral Sr/Ca analytical method using an inductively coupled plasma optical emission spectrometer which

This work provides a rare quantification of lateral spreading from Lagrangian measurements in a buoyant river plume by comparing four methods. Drifter motions, including along‐stream shear and rotation, can be incorrectly interpreted as lateral spreading. This work aims to improve estimates of lateral spreading by identifying additional motions in drifter trajectories. The techniques applied are first

Numerical models are a suitable tool to quantify impacts of predicted climate change on complex ecosystems but are rarely used to study effects on benthic macroalgal communities. Fucus vesiculosus L. is a habitat‐forming macroalga in the Baltic Sea and alarming shifts from the perennial Fucus community to annual filamentous algae are reported. We developed a box model able to simulate the seasonal

Given the severe implications of climate change and ocean acidification (OA) for marine ecosystems, there is an urgent need to quantify ecosystem function in present‐day conditions to determine the impacts of future changes in environmental conditions. For tropical coral reefs that are acutely threatened by these effects, the metabolism of benthic communities provides several metrics suitable for this

Aseptic technique has historically served as a fundamental practice in microbiology, helping to maintain culture purity and integrity. This technique has been widely encouraged and employed for use with cultures of heterotrophic bacteria as well as freshwater and marine algae. Yet, recent observations have suggested that these approaches may bring their own influences. We observed variations in growth

Dinitrogen (N2) fixation is an important source of biologically reactive nitrogen (N) to the global ocean. The magnitude of this flux, however, remains uncertain, in part because N2 fixation rates have been estimated following divergent protocols and because associated levels of uncertainty are seldom reported—confounding comparison and extrapolation of rate measurements. A growing number of reports

Summertime upwelling of deep, corrosive waters on the continental shelf of the northern California Current System can exacerbate ocean acidification conditions, providing unsuitable environments for development of calcifying organisms and finfish that are important to the local economy. To better understand the carbonate system in this dynamic region, two recently developed technologies were combined

210Bi (t1/2: 5.01 d)—the daughter of 210Pb and parent of 210Po—has rarely been measured in aquatic systems, and its behavior in the water column is poorly understood. In this article, I present a method for quickly measuring 210Pb, 210Bi, and 210Po in aquatic samples, where (1) 210Bi and 210Po are scavenged onto an anion solid‐phase extraction disk within 15 min of pretreating the sample; (2) beta

Inconsistency in taxonomic identification and analyst bias impede the effective use of diatom data in regional and national stream and lake surveys. In this study, we evaluated the effect of existing protocols and a revised protocol on the precision of diatom species counts. The revised protocol adjusts four elements of sample preparation, taxon identification and enumeration, and quality control (QC)

Chlorophyll fluorometry is one of the most commonly implemented approaches for estimating phytoplankton biomass in situ, despite documented sources of natural variability and instrumental uncertainty in the relationship between in vivo fluorescence and chlorophyll concentration. A number of strategies are employed to minimize errors and quantify natural variability in this relationship in the open

Headwater streams are important in the carbon cycle and there is a need to better parametrize and quantify exchange of carbon-relevant gases. Thus, we characterized variability in the gas exchange coefficient (k 2) and dissolved oxygen (O2) gas transfer velocity (k) in two lowland headwaters of the River Avon (UK). The traditional one-station open-water method was complemented by in situ quantification

Particulate organic carbon (POC) represents a small portion of total carbon in the ocean. However, it plays a large role in the turnover of organic matter through the biological pump and other processes. Early on since the development of the POC measurement technique in the 1960s, it was known that dissolved organic carbon (DOC) adsorbs and is retained both on and in the filter. That retained DOC is

Zooplankton dominate the abundance and biomass of multicellular animals in pelagic marine environments; however, traditional methods to characterize zooplankton communities are invasive and laborious. This study compares zooplankton taxonomic composition revealed through metabarcoding of the cytochrome oxidase I (COI) and 18S rRNA genes to traditional morphological identification by microscopy. Triplicates

Coring is one of several standard procedures to extract sediments and their faunas from open marine, estuarine, and limnic environments. Achieving sufficiently deep penetration, obtaining large sediment volumes in single deployments, and avoiding sediment loss upon retrieval remain problematic. We developed a piston corer with a diameter of 16 cm that enables penetration down to 1.5 m in a broad range

This work assesses the components contributing to the combined uncertainty budget associated with the measurement of the Fe amount content by flow injection chemiluminescence (FI-CL) in <0.2 μm filtered and acidified seawater samples. Amounts of loaded standard solutions and samples were determined gravimetrically by differential weighing. Up to 5% variations in the loaded masses were observed during

Diatoms require silicic acid to construct ornately detailed cell walls called frustules. The growth and geographic distribution of diatoms is often controlled by the availability of silicic acid. Analytical methods exist to assess diatom community biogenic silica (bSiO2) production, but partitioning production among taxa has been largely qualitative. We present a method for the quantitative analysis

Over the past four decades, mesocosm studies have been successfully used for a wide range of applications and have provided a lot of information on trophic interactions and biogeochemical cycling of aquatic ecosystem. However, the setup of such mesocosms (e.g., dimensions and duration of experiments) needs to be adapted to the relevant biological processes being investigated. Mixing of the water column

Harmful algal blooms (HABs) are a serious public health risk in coastal waters. As the intensity and frequency of HABs continue to rise, new methods of detection are needed for reliable identification. Herein, we developed a high-throughput, multiplex, bead array technique for the detection of the dinoflagellates Karenia brevis and Karenia mikimotoi. The method combined the Luminex detection system

Zooplankton organisms with short generation times, such as rotifers, are ideal models to study general ecological and evolutionary questions on the population level, because meaningful experiments can often be completed within a couple of weeks. Yet biological analysis of such populations is often extremely time consuming, owing to abundance estimation by counting, measuring body size, or determining

Studies using culture dependent methods have indicated that enterococci, the fecal indicator used to monitor marine waters for the potential of enteric disease risk to swimmers, can be abundant in beach sands and may contribute to water column indicator exceedances. A quantitative PCR (qPCR) method for the Enterococcus genus was tested and applied to more rapidly determine the amount of enterococci